param.watch cannot handle parameters from Parameterized, unlike @param.depends

#### ALL software version info
param 1.12.2

run in powershell prompt using panel serve running Bokeh server 2.4.3 on Tornado 6.2

run in VS Code jupyter notebook
Version: 1.76.2 (user setup)
Commit: ee2b180d582a7f601fa6ecfdad8d9fd269ab1884
Date: 2023-03-14T17:55:54.936Z
Electron: 19.1.11
Chromium: 102.0.5005.196
Node.js: 16.14.2
V8: 10.2.154.26-electron.0
OS: Windows_NT x64 10.0.19045
Sandboxed: No

#### Description of expected behavior and the observed behavior

When using the decorator @param.depends() it is possible to use a parameter from another class that is stored as a Parameterized instance in the current class, similar as described in this thread --> [Holoviz Discourse: Shared Parameter?](https://discourse.holoviz.org/t/shared-parameter/2840)
However, trying the same with the lower-level self.param.watch() yields an error message.

In the example below, the decorated function works, while the param.watched throws an error on executing the cell comprising `anB = Bclass(otherclass=anA)`. If the "param.watch'ed" function is changed to a decorated, then again everything works fine.

Am I missing something? Should the behaviour not be the same?

#### Complete, minimal, self-contained example code that reproduces the issue

```
import param

class Aclass(param.Parameterized):

Aa = param.Integer(12)
Ab = param.String("qwe")

def __init__(self, **params):
super().__init__(**params)

def incrAa(self):
self.Aa += 1

def moreAb(self):
self.Ab += self.Ab

class Bclass(param.Parameterized):

theA = param.Parameterized()
Ba = param.Integer(3)
Bb = param.String("asd")

def __init__(self, otherclass: param.Parameterized, **params):
self.theA = otherclass
super().__init__(**params)
self.param.watch(self.moreAtoB, ['theA.Ab'], queued=True, precedence=1)

@param.depends('theA.Aa', watch=True)
def addAtoB(self):
print("\nBclass - self.theA.Aa: ", self.theA.Aa)

def moreAtoB(self, *events):
print("\nBclass - self.theA.Ab: ", self.theA.Ab)

anA = Aclass()
anB = Bclass(otherclass=anA)

anA.incrAa()
anA.moreAb()

```

#### Stack traceback and/or browser JavaScript console output

> Traceback (most recent call last):
File "c:\...\envs\...\lib\site-packages\IPython\core\interactiveshell.py", line 3433, in run_code
exec(code_obj, self.user_global_ns, self.user_ns)
File "C:\Users\...\AppData\Local\Temp\ipykernel_4172\3905510252.py", line 1, in
anB = Bclass(otherclass=anA)
File "C:\Users\...\AppData\Local\Temp\ipykernel_4172\3622346801.py", line 10, in __init__
self.param.watch(self.moreAtoB, ['theA.Ab'], queued=True, precedence=1)
File "c:\...\envs\...\lib\site-packages\param\parameterized.py", line 2450, in watch
return self_._watch(fn, parameter_names, what, onlychanged, queued, precedence)
File "c:\...\envs\...\lib\site-packages\param\parameterized.py", line 2457, in _watch
self_._register_watcher('append', watcher, what)
File "c:\...\envs\...\lib\site-packages\param\parameterized.py", line 2392, in _register_watcher
raise ValueError("%s parameter was not found in list of "
ValueError: theA.Ab parameter was not found in list of parameters of class Bclass
>
>During handling of the above exception, another exception occurred:
>
>Traceback (most recent call last):
File "c:\...\envs\...\lib\site-packages\IPython\core\interactiveshell.py", line 2052, in showtraceback
stb = self.InteractiveTB.structured_traceback(
File "c:\...\envs\...\lib\site-packages\IPython\core\ultratb.py", line 1112, in structured_traceback
return FormattedTB.structured_traceback(
File "c:\...\envs\...\lib\site-packages\IPython\core\ultratb.py", line 1006, in structured_traceback
return VerboseTB.structured_traceback(
File "c:\...\envs\...\lib\site-packages\IPython\core\ultratb.py", line 859, in structured_traceback
formatted_exception = self.format_exception_as_a_whole(etype, evalue, etb, number_of_lines_of_context,
File "c:\...\envs\...\lib\site-packages\IPython\core\ultratb.py", line 812, in format_exception_as_a_whole
frames.append(self.format_record(r))
File "c:\...\envs\...\lib\site-packages\IPython\core\ultratb.py", line 730, in format_record
result += ''.join(_format_traceback_lines(frame_info.lines, Colors, self.has_colors, lvals))
File "c:\...\envs\...\lib\site-packages\stack_data\utils.py", line 145, in cached_property_wrapper
value = obj.__dict__[self.func.__name__] = self.func(obj)
File "c:\...\envs\...\lib\site-packages\stack_data\core.py", line 734, in lines
pieces = self.included_pieces
File "c:\...\envs\...\lib\site-packages\stack_data\utils.py", line 145, in cached_property_wrapper
value = obj.__dict__[self.func.__name__] = self.func(obj)
File "c:\...\envs\...\lib\site-packages\stack_data\core.py", line 677, in included_pieces
scope_pieces = self.scope_pieces
File "c:\...\envs\...\lib\site-packages\stack_data\utils.py", line 145, in cached_property_wrapper
value = obj.__dict__[self.func.__name__] = self.func(obj)
File "c:\...\envs\...\lib\site-packages\stack_data\core.py", line 617, in scope_pieces
for piece in self.source.pieces
File "c:\...\envs\...\lib\site-packages\stack_data\utils.py", line 145, in cached_property_wrapper
value = obj.__dict__[self.func.__name__] = self.func(obj)
File "c:\...\envs\...\lib\site-packages\stack_data\core.py", line 106, in pieces
return list(self._clean_pieces())
File "c:\...\envs\...\lib\site-packages\stack_data\core.py", line 130, in _clean_pieces
raise AssertionError("Pieces mismatches: %s" % mismatches)
AssertionError: Pieces mismatches: [{680, 681}, {696, 695}, {708, 709}, {714, 715}]

#### Screenshots or screencasts of the bug in action